Retevis RT21 Generation 2 Two Way Radios 16CH 3000mAh UHF 2 Way Radios VOX Walkie Talkies(10 Pack) Work directly when out of the box and two knob easy to change channel and adjust volume 3000mAh battery support you several days working and reduce charging time and no worry about interrupted by power off FRS frequency with 50 CTCSS/DCS will keep your group communication away from the interference Strong radio shell and durable antenna and belt clips are useful for your long-term use in the future Simple and Convenient return process;1 year radio warranty and 2 month warranty for accessories;30 day return with no questions asked